The present inventor is the owner of two co-pending applications relating to ripper boot improvements, namely, Australian provisional patent application no. 2005904591 and Australian complete patent application no. 2005204264. The first relates to a ripper boot having a replaceable ripping tooth. The ripping tooth includes a shank having tapered sides adapted to be press fit into a correspondingly shaped cavity in the boot so that it is fixed during operation for improved performance and reduced wear and tear. The latter application relates to a ripper boot having a replaceable ripping tooth that is angled upwardly with respect to the ripper boot carrier thereby raising the angle of attack and improving the cleaving effect. The contents of these co-pending applications are incorporated by reference herein.
As mentioned, this invention is useful in any application where extremely hard and abrasive rock is to be penetrated and ripped, for example, in the extraction of precious stones such as opal, typically achieved through use of a bulldozer ripper boot, or in heavier duty operations which require excavators and the like. In each of these circumstances, the ripper boot teeth, loader bucket teeth, etc, need to be strong and wear resistant enough to work the hard rock. Conventional ripper boots tend to break, and apply extremely high loads on machinery.
Conventional ripper boots consist of predominantly two sections, a carrier section for attachment to machinery, for example, to a bulldozer tyne or loader bucket shank, and a tooth section which is typically integrally associated with the carrier section via a weld. In the applicant's abovementioned patent applications, it is proposed that the tooth section be made replaceable. More particularly, the proposed tooth section includes a shank having tapered sides being fixable within a correspondingly shaped cavity associated with the carrier section by way of an interference fit.
The present inventor has realised an effective way of ripping through hard and abrasive ground through use of a high tensile tip. The use of hardened tips on other tools is known, whereby metals such as tungsten are welded to the tips of the tools to make use of its high strength characteristics. However, welding typically causes the temper of the metal surrounding the weld to be compromised, and as a result, it is envisaged that this would not be a suitable manufacturing method for ripper boots used in mining/excavation, as the tips would simply break off at weak spots surrounding the weld during use. When extremely hard rock is encountered, explosives are sometimes used but this is not a useful alternative because of the significant cost associated with blasting operations.
It is therefore an object of the present invention to overcome at least some of the aforementioned problems or to provide the public with a useful alternative.
It is a further object of the present invention to provide an improved ripper boot including a carrier section, an integral or replaceable tooth section, and a high tensile tip adapted to be press fit into the end of the tooth section. This does away with the need for any welds, improves the ripping ability of the tool, increases its service life, and reduces maintenance requirements.